That toothpaste pregnancy test you've seen online is nonsense

Despite what you may have seen on your newsfeed, the hugely popular 'toothpaste pregnancy test' is not a reliable pregnancy test. In fact, Kiwi experts reckon it's just a load of rubbish.

The test has been gathering steam on social media, where droves of women are posting photos of them trying out the method.

The toothpaste test says that if you're pregnant, when you urinate on toothpaste, it'll turn blue and fizz.

The 'science' behind it states that toothpaste detects the presence of the human chorionic gonadatrophin hormone (HCG) produced by pregnant women. The toothpastes has a chemical reaction with this hormone that causes it to and fizz and change colour. However Kiwi scientists say that the supposed chemistry behind the test is wrong.

"I'm sure there's nothing in toothpaste that can specifically detect the HCG hormone," Professor of Chemistry at Auckland University of Technology Allan Blackman says.

Prof Blackman says that the fizzing people see is just the reaction of bicarbonate in the toothpaste with acid in the urine.

There's also not a lot of support from fertility experts to support the toothpaste test.

Professor Neil Johnson, fertility specialist and gynaecologist at Repromed Auckland, described it as "a novel social media publication".

"My initial search reveals nothing in medical literature about it and even our nursing staff have heard nothing about it. I would have expected them too if this was something that had any credibility," Prof Johnson says.

International experts are also sceptical of the toothpaste test and urge women not to take it too seriously.

So once again the message is, don't trust everything you read on social media. And if you think you're pregnant, just buy a test.